1. Field of the Invention
The invention relates to the technical field of a touch panel.
2. Related Art
The manufacturing processes for a five-wire type resistive touch panel are extremely precise, and require the electric field uniformity that is higher than that of the typical four-wire type resistive touch panel. So, the resistance values of the circumferential silver wires must have the very high consistency, or otherwise the nonuniform voltage distribution of the workpiece surface tends to occur, and the coordinate position of the actual touch point is incorrectly judged or even the touch panel fails. The existing improvement is to try to establish the uniform equipotential electric field through the pattern layout of the resistive elements on the circumferential edges. For example, in U.S. Pat. No. 6,593,916, U.S. Patent Publication No. 2006/0119587 and Taiwan Patent Publication Nos. 201032098, 201032119 and 201122945, annular electrode loops constituted by different discontinuous electrodes on the periphery of the touch-sensing region are utilized to improve the potential “ripple” effect generated by the side-frame region.